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Red clouds

  1. Nov 26, 2005 #1
    I've often observed the sky in the late evening and it was dark. But on cloudy days, the sky is actually bright. The housetops appear dark compared to the sky. And the clouds appear in a dark red tone
    Anyone has an explanation for this? Does the light come from earth, from the moon or from the sun directly that makes the sky so bright when it's cloudy?
    Last edited: Nov 26, 2005
  2. jcsd
  3. Nov 26, 2005 #2
    When the sun has crossed the horizon from your vantage point the clouds above you still have a pretty good view of the sun. That means the sun is still shining on them. Remember that the earth is a sphere, the higher you get the more you can see over the edge. Also some light gets refracted and reflected by the atmosphere and essentially wraps around to some extent.
  4. Nov 26, 2005 #3
    Its called a sunset and "GOD AM" explained it correctly. Its just after the sun has set where we cant see the sun but the clouds still can because they are higher up. Heres a picture i took list night of one. In New Zealand we get huge sunsets that look great.


    This one isnt a sunset but it turned into a great one just after the camera went flat. I thought id show you because it looked cool.
  5. Nov 27, 2005 #4
    no i can attest to this observation as well, i've thought about it to no avail.

    i think he's talking about when its roundabout 2-3am, late into the night, so there's no sun lighting the clouds just below the horizon. the clouds do appear a dark red that is v bright compared to, say, a normal cloudless night. freaked me out the first time i saw it.
  6. Nov 28, 2005 #5
    Thanks for your replies.

    Yes, this is actually what I meant . Yesterday, I observed it again at 10:00 PM, especially because it was cloudy and snowing. I'm not speaking of the bright sky when the sun is still there, but when it's really late.
  7. Nov 28, 2005 #6
    Here in Scotland where we have orange street lighting, a town can cast a noticable red glow on the cloud in certain conditions. I have noticed this from my parents house which is a few miles out of town.

    Is that a possible explanation?
  8. Nov 28, 2005 #7


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    You could get the same 'sunset effect' if there's a bright moon below the horizon. Awesome photos, agusta. You should publish a calendar or cards or something.
  9. Nov 28, 2005 #8
    It's called light pollution. If you are in a city, then the street lights and everything else that puts off light gets reflected by the clouds. If you were out in the middle of nowhere where there isn't any stray light, you wouldn't see this effect. Sometimes in Colorado when it snowed at the right rate, you could see clearly for over a half a mile because the snow would reflect so much light.
  10. Nov 29, 2005 #9
    In norway, and other countries far north, we have somethink called norther light. Its particles in the sky that light up in colours :D Quite cool!
  11. Nov 29, 2005 #10
    Yes, I think that's a good explanation. I've heard of astrophysicists of complaining about light pollution which disturbs from observing stars with their telescopes.

    You see the northern light in Norway?! Awesome!
    http://www.tysfjord-turistsenter.no/safari/norsk/Last_ned/Northern_Light2_1024X768.jpg [Broken]
    Last edited by a moderator: May 2, 2017
  12. Nov 29, 2005 #11
    Yes, it rocks! Too bad im living in the south of norway. In the northern parts of norway, its allmost northern light every night! If you havent seen it, its allmost worth to come here and take a look. Its just amazing :D
  13. Jan 29, 2012 #12
    I too have seen very strange red clouds at night, January 28th 2012 3:00 a.m. Far enough from town to be able to see the light pollution orb no lights nearby, the cloud was circular and deep red, whitish around the outsides(barely visible in the darkness) It occupied about 2/3rds of the sky overhead. the light pollution was to the west and the rest of the night sky was black as pitch in all directions. I have been searching for pictures of this phenomenon but so far have found nothing but this one thread.

    If anyone has any more suggestions what could cause this it would be greatly appreciated.
  14. Jan 29, 2012 #13


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    Is your location north or south of the Equator?
  15. Jan 29, 2012 #14
    I am North of the equator, South western Manitoba, Canada. No northern lights that night, just black sky and a red cloud
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